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the movements of molecules from areas of greater concentration to areas of lesser concentration


the diffusion of water across the cell membrane

active transport

a process that allows molecules to move across the cell membrane from lower to higher concentrations


a process where plants use the energy of sunlight to produce carbohydrates


how we perceive the energy of light


the molecule that absorbs some colors of light and reflects others


the main pigment used in photosynthesis that absorbs blue and red light and reflects green light

cellular respiration

the process in which the chemical bonds of energy-rich molecules are converted into a form of energy that cells can use


a molecule that stores and transfers energy within cells

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